It's shown here: The
gold end of the needle vs
silver end
http://www.diygadget.com/catalog/product/gallery/id/60/image/147/
http://www.diygadget.com/catalog/product/gallery/id/60/image/145/
http://www.diygadget.com/game-console-adapters/usb-binary-extractor-usb-to-com-adapter.html
You always want the tiny silver part to touch the PCB. The gold end of the needle is a little bigger than the silver end. When you buy the USB extractor, the setup is supposed to be done for you already. If both ends of the needle is made of out metal then it should have continuity if you test it with a multimeter.